An attack surface is the total sum of vulnerabilities that can be exploited to carry out a security attack. Attack surfaces can be physical or digital. The term attack surface is often confused with the term attack vector, but they are not the same thing. The surface is what is being attacked; the vector is the means by which an intruder gains access.

HIDS is capable of monitoring the internals of a computing system as well as the network packets on its network interfaces. Host-based firewall is a piece of software running on a single Host that can restrict incoming and outgoing Network activity for that host only.